COG and Balance Point

[Mtwinste]

If my boats starting point COG is 30% how do i measure that in real life? mark that point on the hull, put the batteries in, and hold the boat somehow at that point and see if she balances? what do you hold the boat with at that specific point? seems like some type of dowel rod stand would help with the process?

[properchopper]

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Here's a "quick and dirty" method ; just a piece of angle iron on the boat stand. Works great for hydro's, tunnels, cats. A little tricky for monos, but is workeable.

[siberianhusky]

Dirty at the pond method is a finger at the balance point on each side. Not really that accurate but it works in a pinch.
Unless it's some big 10s 20lb monster!lol

[HYDROJERRY]

Good one Tony,, i never thought of that!!! and will it truly ballance or just real close??

[properchopper]

Good one Tony,, i never thought of that!!! and will it truly ballance or just real close??

Depends on what you mean by "truly". If you kanoodle with it long enough (and don't breathe on it), you'll get to balance perfectly. I don't bother with doing that, given that ride attitude is a mixture of many things besides CG : strut depth & angle, trim tab angle, prop lift, AoA and such. All of which needs playing with for differing water. For example, my setups differ for playwater vs. racewater. SAW water is typically smooth & calm. Sprint racing's a whole 'nother thing

[ksm2001]

Thank you Tony, something so simple and works great.

[properchopper]

Thank you Tony, something so simple and works great.

Yeah, just like my Ex. (till she got religon)

[HYDROJERRY]

OK so if i put the cog say 30 percent on that hull, the hull should not realy tip forward or back,, but if it does just ahair thats close enough because strut angle and all that will finish it up in the water..correct

[properchopper]

OK so if i put the cog say 30 percent on that hull, the hull should not realy tip forward or back,, but if it does just ahair thats close enough because strut angle and all that will finish it up in the water..correct

[Lockk]

OK so if i put the cog say 30 percent on that hull, the hull should not realy tip forward or back,, but if it does just ahair thats close enough because strut angle and all that will finish it up in the water..correct

Exactly what I did I used a 16" long wooden dowel clamped in my vice lined up the hull so its 90 deg to the dowel otherwise your going to cause yourself problems then as mentioned above "kanoodle" with it (for me all I can move in my cat was batteries) till you feel it balancing. I marked the battery location so you can always get back to where your starting point was.